MySQL 4 and Perl scripts

Hi,
Before the MySQL 4 upgrade, we had no problems with any scripts on the server. However, we had to cancel two accounts because each account had a Perl script that would cause MySQL to use all of the CPU it could and stopped all other MySQL sites from loading. We are not having any problems whatsoever with PHP scripts. We cancelled the accounts before the option to downgrade to MySQL 3.23 was available. We would prefer to keep MySQL 4 and wondering if anyone else has experienced the problem and if there is a solution.

I looked at one of the two scripts and it did not even contain one loop in it that could cause it to get into an endless loop and it only contained SELECT statements. This script was executed many times each hour and would cause MySQL to eat CPU resources every 6-12 hours so it did not happen every time the script was executed. I looked at MySQL's full process list and it was executing one of the SELECT statements over and over.